1. Field of the Invention
The present invention relates to a zoom optical system, an optical instrument incorporating the zoom optical system, and a method of manufacturing the zoom optical system.
2. Related Background Art
There are hitherto-proposed zoom optical systems suitable for photographic cameras, digital still cameras, video cameras, and so forth (e.g., cf. Japanese Patent Applications Laid-open No. 8-190051 and Laid-open No. 2005-134870).